Distribution curve of waist-to-height ratio and its association with blood pressure among children and adolescents: study in a large population in an eastern coastal province, China

Waist to height ratio as a screening tool for identifying childhood obesity and associated factors

Objective:

To investigate the prevalence of obesity and associated factors during childhood in Southeastern Turkey. Another objective was to determine the cut-off points of Waist to Height Ratio (WHtR) values for defining obesity/abdominal obesity.

Methods:

The community-based descriptive cross-sectional study was conducted in Gaziantep Turkey between November 2011 and December 2011 with 2718 primary school/high schools students aged 6-17 years. The SPSS 22.00 was used for the analysis of data.

Results:

The prevalence of overweight, obesity, abdominal obesity, was 13.2%, 4.2% ,26.4%, respectively. There was a reverse relationship between BMI/WC values and sleep durations (p<0.05). The BMI/WC values were higher in students with computer usage time ≥1 hours in a day (p<0.05). Parental obesity status has an effective role on the WC/BMI values of children (p<0.05). The WHtR was a good predictor of diagnosis on obesity and abdominal obesity (AUC=0.928, p<0.0001; AUC=0.920, p<0.0001; respectively). The optimal cut-off values for obesity and abdominal obesity were detected as 0.5077, 0.4741, respectively.

Conclusions:

The WHtR can be used for diagnosis of obesity/abdominal obesity. Parental obesity, short sleep duration and computer use more than one hour per day are risk factors for the development of obesity in children and adolescents.

Waist circumference as high blood pressure predictor in school age children

Childhood hypertension is becoming more common with the increasing numbers of child obesity, which has encouraged new studies to identify a good anthropometric marker for high blood pressure levels. The objective this study was to identify the best anthropometric predictor of risk of hypertension in children between 8-10 years of age. The Children were evaluated for socioeconomic status and their blood pressure (BP), weight, height, waist circumference (WC) and percentage of body fat (PBF) were measured. The study included 445 children, of which 50.1% were females. The prevalence of obesity defined by body mass index (BMI) was 14.6%. Increased BP was found in 3.4% and 2.2% of the children, considering the pre-hypertension and hypertension classifications respectively. The arithmetic mean of BP value correlated significantly with BMI, WC and PBF. After height control, the correlations that were maintained significant were between WC and systolic blood pressure (SBP) and between WC and diastolic blood pressure (DBP). The variable with the highest predictive power of the occurrence of hypertension was WC. The results indicate that, in this population of children between 8 and 10 years old, WC is a measurement of higher value in predicting increased BP.

Abdominal obesity and its association with socioeconomic factors among adolescents from different living environments

BACKGROUND

Socioeconomic status has been associated with obesity in children and adolescents. This association may be dependent according with where adolescents lives.

OBJECTIVE

The aim of this study was to evaluate the association between different socioeconomic indicators such as parental education and occupation and socioeconomic status with abdominal obesity in adolescents from two observational studies: the Healthy Lifestyle in Europe by Nutrition in Adolescence cross-sectional study (HELENA-CSS) and the Brazilian Cardiovascular Adolescent Health (BRACAH) study.

METHODS

European (n = 3192, aged 12.5-17.5 years, with 53.1% girls from HELENA-CSS) and Brazilian (n = 991, aged 14-18 years, with 54.5% girls from BRACAH study) adolescents from two cross-sectional studies were included in this analysis. Complete data on waist circumference (WC), height, socioeconomic status indicators and several confounders were collected. Socioeconomic indicators were measured using a self-reported questionnaire in order to assess the family social status of the adolescents. Multilevel linear regression models were used to examine associations, and results were adjusted for potential confounders.

RESULTS

Adjusted results showed inverse associations between mother's and father's education levels (p < 0.001) and father's occupation level (p < 0.001) with waist-to-height ratio (WHtR) and WC in HELENA-CSS girls. Similarly in European girls, socioeconomic indicators by socioeconomic status and maternal occupation level were associated with WHtR. In HELENA-CSS boys, the same significant association was found between WHtR and WC with maternal occupation level. Moreover, in European boys WHtR was also associated with parental education. In Brazilian adolescents, both indicators of abdominal obesity did not remain associated with the independents variables, after adjustment for potential confounders.

CONCLUSIONS

Abdominal obesity was associated with socioeconomic indicators in higher-income countries, but this association was not observed in a lower-middle-income country.

Metabolic syndrome among children and adolescents from Southern Italy: contribution from the Calabrian Sierras Community Study (CSCS)

Among 1657 children and adolescents aged 6 to 14 years (787, 47% girls and 870, 53% boys) from primary and secondary schools in a 14-town Southern Italian community, HDL cholesterol (54 ± 15 mg/dl), triglycerides (61 ± 29 mg/dl), blood glucose (78 ± 10 mg/dl), systolic (101 ± 11 mm Hg) and diastolic (62 ± 10 mm Hg) blood pressures, waist circumference (WC) (66 ± 10 cm) and WC/height (0.46 ± 0.006) and triglycerides/HDL cholesterol (1.31 ± 0.99) ratios were measured. The distributions were similar in both genders. Age did not affect triglycerides/HDL cholesterol ratio, whereas there was a slightly positive correlation (p<0.00001) between WC/height and triglycerides/HDL cholesterol ratios. We present individual gender and age specific percentile distributions (as Supplementary materials). Using percentile cut-offs (≤ 10th for HDL cholesterol and ≥ 90th for the other components), there were 183 (11%) children or adolescents with low HDL cholesterol, 162 (9.77%) with high triglycerides, 178 (10.74%) with high blood glucose, 178 (10.74%) with high WC, 244 (20.76%) with high systolic or diastolic BP and 126 (7.6%) with high systolic and diastolic BP. Abnormally high BP was seen in 470 (28.36%) children or adolescents. Using abnormal percentile values of 3 of 5 of its components, metabolic syndrome (MS) was diagnosed in 70 (4.2%) subjects, similarly in both genders. To assess out-of-limit distributions of all 5 individual MS components in children and adolescents gender- and age-distributions derived from local epidemiological data should be used: these distributions are presented and they might now be used both for comparative and applicative purposes at least in Southern Europe.